The compound a2o is 63.7% a (mystery element) and 36.3% oxygen. what is the identity of element a?

Nitrogen,N

We are given;

We are required to identify A

Atomic mass of O is 16.00 g

Therefore, mass of Oxygen in the compound is 16.00 g

16.00 g = 36.3 %

Thus, mass of A = (16.00 × 63.7%) ÷ 36.3%

                          = 28.077 g

But there are two atoms of A in the compound

Therefore, Atomic mass of A = 28.077 g ÷ 2

                                                = 14.039 g

                                                = 14.0 g

Thus, the identity of element A is nitrogen, because its atomic number is 14.0067 which is approximately 14.0 g

Hence, identity of element A is Nitrogen (N)

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).